1. Field of the Invention
The present invention relates to an arrangement for managing a herd of freely walking animals, comprising an area for receiving the animals, a milking station located in said area and having an exit, means for automatic milking of an animal in the milking station, and a separation device located in said area for separating an animal from the herd. The invention also relates to a method of managing a herd of animals freely walking in a receiving area. Furthermore, in a second aspect of the invention, it relates to an arrangement for managing a herd of freely walking animals, comprising an area for receiving the animals and a separation device located in said area for separating an animal from the herd, said device comprising enclosure means defining a separation zone, and at least one entrance device for permitting passage from the receiving area to the separation zone. Furthermore, in a third aspect of the present invention, it relates to a separation device for separating an animal from a herd of freely walking animals, comprising enclosure means defining a separation zone, and at least one entrance device for permitting passage from an area for receiving the herd to the separation zone, said entrance device comprises a first stall, having a front gate device which in an open state permits passage from the first stall to the separation zone and in a closed state prevents passage between the first stall and the separation zone.
2. Description of the Prior Art
Automatic milking of cows is known. Automatic milking may take place in one or more automatic milking stalls provided in an area in which the animals are allowed to walk about freely and find their way individually to the milking stalls. The cows are automatically identified in each stall with the aid of a computer connected to identification means. By means of the computer, in which facts concerning each cow when she was last milked, etc. are stored, a milking robot is activated. The stall also comprises retaining gates which are automatically closed to retain the cow during milking and opened to let the cow leave the stall. Traditionally, cows are milked twice a day. Because of high labour costs it was not interesting to increase the number of milkings per day as long as milking was performed manually. It is however recognized that milking a cow three to four times a day has proved to be of less detriment to her, since the udder is not filled to its maximum between each milking. Such a milking procedure corresponds more closely to the behaviour of the calves and therefore results in healthier cows. As a side effect, however, it is possible to increase the total milk production from one cow by 15-25% by increasing the number of milkings per day. By means of automatic milking machines it is not only possible, but would also be economically interesting to milk the cows more often than twice a day, since the labour costs are not any longer critical. In this case it is rather the high investment cost which is the limiting factor. Therefore, in order to reach a high utilization of the capacity of such automatic milking machines and in order to reach such a high milking frequency by a reasonable number of automatic milking stations, it is desirable or even necessary to enable the cow to develop a trust in the milking station and the automatic milking machine. Only then she will voluntarily and frequently enter the milking station. In view thereof it is of course very important that she does not associate the milking station with anything which hurts or is disagreeable to her.
In order to find out if milking of a cow entering the milking station should be performed, she must be examined to find out whether there is any hinder to milking, for example the cow may be infected by a disease, blood might come in the milk, or the udder and the teats might be injured. Such illness or defects should be treated and cured before the cow can participate in the normal milk production. However, such treatment may hurt the cow or at least be disagreeable to her. Therefore, the performance of such treatment is a negative experience for the cow, which she, due to her very good memory, certainly will remember. Consequently performing such treatment in the milking station may lead to the cow associating the milking station with a negative experience. This makes the milking station less attractive to the cow and therefore in a system based on voluntariness she might not visit the milking station as often as would be desirable in order to reach a high total milk production per day.
It has been proposed in the past to provide means for separating the cow from the milking station to a separation area, in which medical treatment of the cow may take place. Also in this case the cow may associate the milking station with a negative experience of the medical treatment, since she is treated directly after being transferred from the milking station.
It is also known to provide a separation device for separating an animal from an area receiving a herd of freely walking animals, comprising a separation zone, enclosed by enclosure means, and at least one entrance device for permitting passage from said receiving area to the separation zone.
WO-A-8704898 discloses a method and a device for separating selected animals from a herd. To this end, the animals are brought to a sluice comprising a computer for identification and controlling feed distribution, and additional devices for the control of outlets or passages. The separation of selected animals is obtained by the outlets and passages being movable to close and open different outlet areas.
U.S. Pat. No. 5,183,008 discloses a livestock sorting system having an entrance with an identification sensor and first and second aisles extending from the entrance. An automatically controlled gate is actuated between two positions to lead the livestock to either of the two aisles.
DE-C-3 702 465 discloses a method and a device for milking and feeding freely walking cows carrying an identification device. The cows are identified and led to a gate which may be in two positions opening to the milking stalls or the feeding stalls. A cow to be milked is led to the milking stalls and the cows which should not be milked are led to the feeding stalls or back to the free walking area.
SU-A-1 813 383 discloses a separation device comprising enclosure means defining a separation zone, and at least one entrance device for permitting passage from an area to the separation zone. The entrance device comprises a stall, having a front gate device which in an open state permits passage from the stall to the separation zone and in a closed state prevents passage between the stall and the separation zone.